In a laminar 2-D flow of viscous fluid Couette flow is defined asa)As...
Couette flow is defined as a flow of very small value of Reynold's number between two plates, one is fixed and the other is moving.
Hence, the correct option is (D)
View all questions of this test
In a laminar 2-D flow of viscous fluid Couette flow is defined asa)As...
Couette flow in laminar 2-D flow of viscous fluid is defined as the flow between a fixed and a moving plate. Let's understand this definition in detail.
Definition of Couette Flow
Couette flow is a type of laminar flow between two parallel plates, where one plate is fixed and the other plate is moving. This flow is named after Maurice Couette, a French physicist who first observed this type of flow in 1890.
Explanation of the Definition
To understand the definition of Couette flow, we need to understand laminar flow, viscous fluid, and parallel plates.
- Laminar Flow: Laminar flow is a type of fluid flow where the fluid particles move in parallel layers without any mixing or turbulence. This type of flow occurs at low velocities and low Reynolds numbers.
- Viscous Fluid: A viscous fluid is a fluid that has a high resistance to flow and tends to deform under shear stress. Examples of viscous fluids include honey, oil, and molasses.
- Parallel Plates: Parallel plates are two flat plates that are parallel to each other.
Now, let's combine these three concepts to understand the definition of Couette flow.
In Couette flow, we have two parallel plates, one of which is fixed and the other is moving. When we apply a shear stress to the fluid between these two plates, the fluid particles start moving in parallel layers, creating a laminar flow. The moving plate drags the fluid particles with it, while the fixed plate holds the fluid back. This creates a velocity gradient between the two plates, with the velocity being zero at the fixed plate and increasing linearly with distance from the fixed plate towards the moving plate.
Applications of Couette Flow
Couette flow has many practical applications, such as in the lubrication of bearings, the mixing of fluids, and the coating of surfaces. It is also used in experiments to study the rheological properties of fluids, such as viscosity and shear stress.
Conclusion
In summary, Couette flow is a type of laminar flow between a fixed and a moving plate, where the fluid particles move in parallel layers without any mixing or turbulence. This flow is important in many practical applications and is used in experiments to study the properties of viscous fluids.